<div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102)">Dear John,<br></div><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102)">Even we face same problem. Our Dry etch and PECVD tools drink more N2 than any other pumps in the clean room. <br>
</div><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102)">We found our DRIE tool has an inbuilt software option which restricts the pump N2 flow during stand by mode, which is really helping us to save a lot of N2. For the same option we had a long discussion with our RIE and PECVD manufacturer; recently we got to know that they also developed a software for the same, which we still need to purchase and install. <br>
For your tools you may need to talk to the manufactures if they have any option as such. <br></div><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102)">So as Fouad mentioned that would be great if the all the manufactures work on this.<br>
<br></div><br><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102)"><font style="font-family:verdana,sans-serif;color:rgb(0,0,102)"><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102);display:inline">
</div>Thanks & Regards,<br><br><i><b>Vamsi Krishna</b></i><br>Sr.Facility Technologist - Dry Etch & <font>P<font><font>rocess</font> Integration</font></font><br>National Nano Fabrication Center<br><span>Center for Nano Science and Engineering (CeNSE)<br>
Indian Institute of Science(IISc)<br>Banga<font>lore<font> </font></font>560012, <font>INDIA</font></span><br>Mobile: +91 9880988239</font><br><br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Apr 12, 2013 at 1:16 AM, Lavallee, Guy P. <span dir="ltr"><<a href="mailto:gpl107@psu.edu" target="_blank">gpl107@psu.edu</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">John,<br>
I believe the issue with the Fluorine chemistries is the formation of HF if you ever have water in the CDA which then gets into the pumps. The potential of creating this would obviously be dependent on how much unreacted fluorine would reach the pump as well as how reactive the effluents would be with water leading to the formation of HF.<br>
<br>
The other issue you have to think about besides water (which the pumps won't like either regardless of HF formation) would be the potential of oil being in the CDA. This will be highly dependent on the type of CDA system you have at your facility.<br>
<br>
We have thought about changing from N2 to CDA as well but have been very hesitate due to the many unknowns and not wanting to risk it. It would be interesting to hear others inputs.<br>
<br>
Thanks,<br>
Guy<br>
<br>
Penn State University's Nanofabrication Laboratory<br>
Lead Etch Engineer<br>
Materials Research Institute<br>
N-105 Millennium Science Complex (MSC Bldg)<br>
University Park, PA 16802<br>
Email: <a href="mailto:gpl107@psu.edu">gpl107@psu.edu</a><br>
Phone: <a href="tel:814-865-9339" value="+18148659339">814-865-9339</a><br>
Cell: <a href="tel:814-777-0719" value="+18147770719">814-777-0719</a><br>
<div class="im"><br>
<br>
-----Original Message-----<br>
From: <a href="mailto:labnetwork-bounces@mtl.mit.edu">labnetwork-bounces@mtl.mit.edu</a> [mailto:<a href="mailto:labnetwork-bounces@mtl.mit.edu">labnetwork-bounces@mtl.mit.edu</a>] On Behalf Of John Shott<br>
</div><div class="im">Sent: Thursday, April 11, 2013 11:48 AM<br>
To: Labnetwork<br>
Subject: [labnetwork] Using CDA, rather than N2, as pump purge in Bosch-like processes?<br>
<br>
</div><div class=""><div class="h5">Labnetwork Community:<br>
<br>
Like many of you, I suspect, nitrogen is the single largest non-salary expense associated with running our facility.<br>
<br>
Much of our nitrogen is used for pump purges in dry pumps. Our average dry pump seems to use about 1 CFM (sorry, 25-30 SLM ...) which, at our pricing is about $4k per year. For virtually all deposition processes using reactive gases and etch processes using corrosive gases, using nitrogen as a pump purge seems to be a firm requirement. It is not as obvious, to me at least, that nitrogen is required in something like a SF6/fluorocarbon-based etch process like the switched Bosch processes that many of us run. While I know that CDA isn't "free", in our case, the LN2 bill definitely comes out of our pocket whereas as CDA is a University supplied and supported building utility.<br>
<br>
What experience, recommendations, or cautions can you offer related to switching our Bosch process tools from nitrogen to CDA pump purges? If it matters, the dew point of our CDA is believed to be less than -40 C, but is not monitored continuously (and maybe not even monitored periodically ...).<br>
<br>
Thanks for your consideration,<br>
<br>
John<br>
<br>
<br>
<br>
<br>
_______________________________________________<br>
labnetwork mailing list<br>
<a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a><br>
<a href="https://www-mtl.mit.edu/mailman/listinfo.cgi/labnetwork" target="_blank">https://www-mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a><br>
<br>
_______________________________________________<br>
labnetwork mailing list<br>
<a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a><br>
<a href="https://www-mtl.mit.edu/mailman/listinfo.cgi/labnetwork" target="_blank">https://www-mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a><br>
</div></div></blockquote></div><br><br clear="all"><br>-- <br><font style="font-family:verdana,sans-serif;color:rgb(0,0,102)"><div class="gmail_default" style="font-family:verdana,sans-serif;color:rgb(0,0,102);display:inline">
</div>Thanks & Regards,<br><br><i><b>Vamsi Krishna</b></i><br>Sr.Facility Technologist - <font>P<font><font>rocess</font> Integration</font></font><br>National Nano Fabrication Center<br><span>Center for Nano Science and Engineering (CeNSE)<br>
Indian Institute of Science(IISc)<br>Banga<font>lore<font> </font></font>560012, <font>INDIA</font></span><br>Mobile: +91 9880988239</font><br><br style="font-family:verdana,sans-serif"><font style="font-family:verdana,sans-serif" size="1"><i><font style="font-family:verdana,sans-serif;color:rgb(0,0,102)">A bird sitting on the branch of a tree is not afraid of the branch shaking or breaking, because it trusts not the branches but its OWN WINGS.<br>
<br></font></i></font>
</div></div>